Floating solar panel test beds in the district of San Antonio in Laguna de Bay, Philippines. Solar power firms like Ciel et Terre are asking regulators for 10 per cent use of the 95,000 hectare lake, translating to over 9,000 megawatts of renewable energy for the country. Image: Sun Asia Energy
An array of solar panels floats on the waters of San Antonio in San Pedro, one of the cities surrounding Laguna de Bay, the Philippines’ largest freshwater lake 55 kilometres south of Metro Manila, on the northern island of Luzon.
Installed in March by renewable energy firms Sun Asia Energy and Ciel et Terre, the 13 kilowatt structure is a year-long experiment to see if the photovoltaic (PV) panels can withstand the strong waves and gusty winds at the lake.
In the nine months since it was installed, the test bed has survived more than 10 typhoons that have slammed into Luzon, said Karlo Abril, Sun Asia’s floating solar project lead. They included Typhoon Mitag—the most powerful typhoon in the country this year with a wind speed of up to 170 kilometres per hour, and which also caused fatalities in Japan, China and South Korea.
Screw piles used to anchor the aluminium frame modules in the solar PV test bed in Laguna de Bay. Image: Sun Asia Energy Inc
Aware of the 911-square-kilometre lake’s exposure to extreme weather, developers have used a screw piling method for the modules carrying the solar panels, to allow them to move more freely in waves.
Apart from the anchors, installers have attached recyclable polyethylene frames that cradle the solar panels and are able to withstand winds of up to 118 miles per hour.
The San Antonio test bed is one of the five floating solar pilot installations in the Philippines, mostly set up in the waters of Laguna de Bay.
Solar energy companies in the Philippines have started turning to lakes and dams to install solar arrays as part of the government’s wider push for 2,000 megawatts in installed capacity of renewable energy in 10 years.
Abril fancies the potential of floating solar in the Philippines, an archipelago of more than 7,100 islands, with over 200 hectares of lakes and 19 hectares of water reservoirs.
“The Philippines has a potential of 11 gigawatts of inland floating solar if it covers just 5 per cent of the country’s water surface, which can power up to 7.2 million households,” he told Eco-Business. “Offshore floating solar may be the solution for islands with limited available land areas. “
Embracing its vulnerability to typhoons
If solar arrays can withstand conditions in a country that is hit by an average of 20 typhoons per year, the technology can survive less treacherous conditions in other countries, said Dr Thomas Reindl, deputy chief executive of the Solar Energy Research Institute of Singapore.
SERIS deputy chief executive officer Thomas Reindl speaking at the 4th ASEAN Solar + Energy Storage Congress in Muntinlupa City, Philippines. Image: ASES
“Most floating solar projects I’ve seen are done in calm waters as it’s the easiest way of deploying them. Very few countries have floating solar deployed right away in strong winds like the Philippines,” Reindl told Eco-Business on the sidelines of a floating solar conference at Muntinlupa City in the Philippines this month.
“The Philippines should embrace being prone to typhoons and use the
situation as a source of knowledge for research to develop solutions and
sell the expertise to other countries which also have strong winds,
like Japan, Taiwan and South Pacific Islands.”
In Japan and Taiwan, floating solar systems typically use steel or concrete structures to be typhoon-safe, but they are “10 times more expensive than the plastic floaters being used for floating solar technology”, said Reindl.
“The Philippines’ competitive advantage would be to come up with a solution that would work with strong winds and is, at the same time, cost-effective,” he said.